Shield Inlay's Tutorial

This tutorial will show how to use the shields and shield templates cut by Great Lakes Waterjet, inc and sold by Midwest Knifemakers Supply,llc. These can be seen and purchased by clicking >HERE<


These shield templates are cut from 1095 in 1/8" thickness. They are not hardened but don't need to be. They are approximately 3"x1"x1/8"

The shields (there are nearly 30 different designs) are 410SS in .048" thickness. These will need some clean up before they are used. Each will need to be deburred and the reside tab from waterjetting sanded off. In practice, this is just a couple of swipes on a piece of sandpaper, top, bottom and tab. Don't take off too much. Just a enough to remove the tab and deburr it.


First lets look at materials:



today I am using a typical dremmel rotary tool with the optional cutting attachment. The cutting attachment allows the dremmel to act like a router machine and has adjustable up and down setting. It was ten bucks I think.



It just screws on and off.


I am using Cyanacrolate (CA is superglue) to glue the shield template in place. I have the location marked exactly where I want it. I am practicing on a piece of carmel-brown micarta This will also work for most any other material.
I glue the template in place with CA. A couple dots on the micarta and some accelerator sprayed on the template. This cures the CA in just seconds for less chance of movement.
Just one dot of CA on each side of the location, a spray of accelerator on the template and press down. The template will be removed later by just giving it a couple taps with a hammer on the back side of the micarta. It will pop right off. I grind off any residue CA left on the template or use CA remover.



Here it is all set up and cutting.

There is a an opening you can look through. I have it sitting on the bench here but you can hold it in your hand and move the piece all around to see inside of the cut out.



Here is a view looking into the cut out. The technique is to plunge the cutting burr multiple times to hog out the inlay opening. Once you have most of the material removed, you start moving the cutter back and forth cutting out the remaining webbing. Here is a look inside and you can see some of the plunge cuts still left and most of the material has been removed.
I am using a 3/64" needle burr , this can be compared to Dremel #112 burr. Note I have scribed which side goes up on the template. This is important. A waterjet will cut material at a slight angle and not straight up and down. The angle will become more pronounced with the thickness of the material and the speed of the cutting. This is almost never a problem. Here it is an advantage. When inspecting the template shield, one side will have a slightly smaller opening than the other side. This will be very slight maybe .001" to .002". The narrow side should be on top. This allows the cutting burr to ride along the burr shaft instead of the cutting burrs hitting the shield.


The burr's have a slight taper from the shaft size to the burr size. Adjusting the depth of the burr allows the narrow opening of the shield to ride against the tapered shaft of the burr. This very slight taper and the narrow/wide opening of the shield allow for a very precise fit of the inlay shield. It's trial and error to fit it but it's just not that much work.
To adjust this one, I simply eyeballed and got it after one adjustment.


You can, if you want skip all of this and simply free hand the dremel tool. I did that to one and it turned out just fine.


You might have to grind a little off the end of the needle burr to make the cutting edges of the burr shorter AND therefore easier to have the shaft ride along the template. If you find the depth of your cut is too deep, grind a little off the cutting burr end.

Here is what a clean cut looks like...


A tap or two on the back side of the micarta and the shield pops right off. Here is the inlay opening with a shield ready to be put in place.


This is a snug fit. I will tap this in place with a hammer since this is micarta. If it was wood, I will want a slightly larger opening. I could tap this in place into wood and it would not split right away but it would split over time. Look at old knives that have pins or inlays. It is very common to see a crack radiating from the pin or the inlay. This isn't because it was too close to the edge. It was because the fit was too tight and over time, the natural movement of the material and the constant stress of the inlay will crack the material. That won't happen with this micarta. It's too tough and the fit in this case isn't too tight.


Here it is tapped in place with a hammer. See how tight the fit looks? It will look even better in a minute.


Now I have sanded it with 80 grit. Any seam you might have seen before is gone.


I have buffed it and waxed it. The seam is invisible and the shield is nice and shiney.


This is the basic process for all inlays using a positive template to create the inlay opening. You can of course, use the shield in a fixture with a milling machine (or even a drill press if you can lock it into place).
The needles gravers are a few bucks apiece and dull quickly. I would use one for a couple jobs - if that and toss it for a new one. It is a consumable. The 3/64" will fit all the tight corners for the shields. I didn't show it but you would use a drop of CA on most material in the cavity before tapping in the inlay.






I'd welcome any other pictures, comments or suggestions about doing an inlay here in this thread.
Thanks for looking
t

I've been contemplating how to go about doing this. Thanks a million for posting this Tracy.

This is insanely easy with the pre-made shields and templates. Seriously. The piece I did free hand (no cutting attachment on the dremel) turned out just fine.

Nicely done. I'll have to start adding those to my slipjoints I think.

Damn, more money. I got a heap of those shields but didnt see the templates before.

Bruce Barnett said:

Damn, more money. I got a heap of those shields but didnt see the templates before.

Click to expand...

the templates make it a snap...they are a must have..

Very cool Tracy!!2thumbs

I was just getting ready to try this out on some scrap for the first time before I try it on a knife handle but had a couple of questions.

Do you clean up all the water jet edges on the shield before you do the inlay so the shield will just pass through the template. My trial one goes about 1/4 of the way in at the moment.

Also my template has a bit of a divot out of it along one of the smooth edges where it looks like the water jet started the cut any ideas on keeping the inlay smooth along that edge? My first practice ones will be on some G10 so if there is some stress because I went inside the edges it won't matter too much but once I go onto mammoth ivory, bone and MOP it will be really important.

Alistair

a quick rub on a flat piece of sand paper will knock off the burr.
If the divot is a deal breaker, let me know and i'll replace it.

This is why I love the forum and usaknifemaker's store. You are about 1000x better than the last supplier I dealt with. I'll give it a go ignoring the divot on some scrap and see how it goes.

Alistair

I gave it a go today but the super glue gave way when I was going around the edges and stuffed things up, at least it was only some scrap I was practicing on. I might have to get one of those hold down clamp thingys you have. I am also going to HT my template I was too paranoid of wrecking the template.

Alistair

Hey Alistair,
Which number sheild is it, i might have a template here?? Ive got one of the clamps too if ya need to borrow it until yours gets in.
If ya grind back the end of the cutting bit so you only have the depth ya want left, then just the straight shaft will be running against the template, so you shouldnt need to heat treat.
Cheers Bruce.

Is there any way for the photos to be re-loaded on this thread. I have ordered 2 templates and want to give this a try. Thanks

WG44

Boss I have a template and shields also and would love to see the tutorial, if you can load it again.

i can't see the images, they're broken, anybody else has the same problem?

I can't see it either maybe they will put it back up I would love to see it.

not sure what happened. I will have to dig around and see if I can find those pictures.

Thanks a lot Tracy